Bottom line there is I suspect it was mainly a throwback to the days of sail – black and white or black and yellow was just the colour ships were meant to be, and the whole superstructure thing was a bit of a new development .

Dom, that is great, it helps a lot with the details. I was hoping that there was an accessible sectional drawing. That hull is not your garden variety shape and having a set of sections every 5 or 10 meters would really help. Most of the photos that I have been able to find are not the best quality.

Gildas, Lilac! It might not be too far off for the French, most everybody ditched the black hull thing a little later, and I understand that camouflage on a ship that is spewing a column of black coal-smoke is frankly silly. Later upperworks were often gray or white. I was thinking that it was just stupid a fad, like picklehaubes after the Franco-Prussian War. That, or there was something special about the yellow paint that made cleaning all that soot off of it a little easier.

The buff and black shows her pre WW1. On colonial service the hull would have been white, in home waters it was as shown.

The grey with black hull as shown, was adopted just after the Russo Japanese war. The navies of the world had seen from the Spanish American war, the Sino Japanese and Russo Japanese wars, that the older schemes were unsuited to an era where ships engaged at longer ranges and often fought at night.

The Russians even used cinnamon over all, or black over all. (Somewhat spoilt at Tsushima where the funnels of the Russian ships were bright yellow to identify them from the Japanese who were expected to have black hulls)(They did not and were a dull grey all over without any attempt at smartness.)

The French and Spanish clung to black hulls for some time as did the Russians. However by WW1 the scheme had given way to plain old grey, the first over all camouflage since scout ships of Republican Rome that were painted pale blue to make them hard to see on the horizon.

The principle of a dark hull did remain. Some nations used dark grey hulls and during WW2 dark blue lower hull areas became popular.

The early scheme shown for Dupuy du Lome was not about hiding a ship, but rather about making it looks smart and efficient when impressing foreign dignitaries or over awing colonial natives!